Difference between revisions of "Knopp function"

From specialfunctionswiki
Jump to: navigation, search
Line 4: Line 4:
  
 
=Properties=
 
=Properties=
<div class="toccolours mw-collapsible mw-collapsed">
+
[[Knopp function is continuous]]<br />
<strong>Theorem:</strong> The [[Knopp function]] $K_{a,b}$ is [[continuous]] on $\mathbb{R}$ for $a \in (0,1)$ and $ab>1$.
 
<div class="mw-collapsible-content">
 
<strong>Proof:</strong> █
 
</div>
 
</div>
 
  
 
<div class="toccolours mw-collapsible mw-collapsed">
 
<div class="toccolours mw-collapsible mw-collapsed">

Revision as of 03:31, 27 October 2016

Let $a \in (0,1)$ $ab > 1$. Define the Knopp function $K \colon \mathbb{R} \rightarrow \mathbb{R}$ by $$K_{a,b}(x)=\displaystyle\sum_{k=0}^{\infty} a^k \mathrm{dist}_{\mathbb{Z}} \left( b^k x \right),$$ where $\mathrm{dist}_{\mathbb{Z}}$ denotes the distance to integers function.

Properties

Knopp function is continuous

Theorem: The Knopp function $K_{a,b}$ is nowhere differentiable on $\mathbb{R}$ for $a \in (0,1)$and $ab > 1$.

Proof:

See Also

Takagi function
van der Waerden function

References

[1]